Method and system for detecting light transmission of optical thin film

Abstract

The invention relates to the technical field of light transmittance detection, in particular to a light transmittance detection method and system for an optical thin film, and the method comprises the steps: selecting a standard sample of the optical thin film, scanning the standard sample at a preset first resolution, and obtaining the light transmittance and haze of the standard sample at each measurement point; the method comprises the following steps: performing primary global scanning on a to-be-measured optical thin film at a preset second resolution to obtain light transmittance and haze of the to-be-measured optical thin film at each measurement point in the first scanning so as to determine an abnormal evaluation value of a local area, and screening out an abnormal area; and performing secondary scanning on the abnormal area at a preset first resolution, and generating a light transmittance distribution diagram and a haze distribution diagram covering the whole optical thin film to be detected based on the light transmittance and the haze of all the measurement points corresponding to the two times of scanning so as to detect the light transmittance of the optical thin film to be detected. The detection efficiency is remarkably improved while the detection precision is guaranteed, and the overall performance and reliability of optical thin film detection are effectively improved.

Description

Technical Field

[0001] This application relates to the field of light transmittance detection technology, specifically to a method and system for detecting the light transmittance of optical thin films. Background Technology

[0002] In high-end manufacturing fields such as automotive displays and precision optical components, the light transmittance of optical films is one of the key indicators for measuring product quality. Light transmittance not only affects the optical performance of the film, but also directly relates to its performance in practical applications. If the light transmittance of the film is insufficient or the haze is too high, it will lead to uneven display brightness, dark spots or glare, which will seriously affect the visual effect and yield of the end product.

[0003] Traditional transmittance testing mainly uses the integrating sphere method. However, the measuring spot of the integrating sphere is usually very small, and each measurement can only obtain transmittance data at a single point. For large-area optical thin films, if low-resolution scanning is used, the measurement points are sparse and limited, which cannot represent the transmittance of the entire film. It is easy to miss irregularly distributed scratches, dirt, or uneven coating and other defects, resulting in insufficient detection accuracy. On the other hand, if the entire film is scanned at high resolution point by point, the large number of measurement points will lead to long detection time and low detection efficiency. Summary of the Invention

[0004] To address the aforementioned technical problems, a method and system for detecting the transmittance of optical thin films are provided to resolve the existing issues.

[0005] The solution to the technical problem of this application is to provide a method and system for detecting the transmittance of optical thin films, including the following steps: In a first aspect, embodiments of this application provide a method for detecting the transmittance of an optical thin film, the method comprising the following steps: A standard sample of optical thin film is selected and scanned at a preset first resolution to obtain the transmittance and haze of the standard sample at each measurement point; For the optical thin film under test, a multi-level scanning strategy is executed, the strategy including: First, a preliminary full-area scan of the optical film under test is performed at a preset second resolution to obtain the transmittance and haze of the optical film under test at each measurement point in the first scan. For each measurement point after the first scan, the fluctuation of transmittance and haze in the local area is used to assess the abnormality of the local fluctuation, determine the abnormal assessment value of the local area where each measurement point is located, and screen out abnormal areas. Then, the abnormal area is scanned a second time at a preset first resolution. Based on the transmittance and haze of all measurement points corresponding to the two scans, a transmittance distribution map and a haze distribution map covering the entire optical film under test are generated to detect its transmittance.

[0006] Preferably, the preset first resolution is greater than the preset second resolution.

[0007] Preferably, determining the abnormal assessment value of the local area where each measurement point is located includes: calculating the abnormal assessment value of the local area where each measurement point is located by measuring the degree of deviation of the changes in transmittance and haze at all measurement points in the local area where each measurement point is located after the first scan relative to the standard sample.

[0008] Preferably, one calculation process for the anomaly assessment value is as follows: Analyze the deviation ratio of the transmittance of all measurement points in the local area where each measurement point is located after the first scan from the transmittance of all measurement points on the standard sample, and calculate the relative fluctuation of transmittance. Analyze the deviation ratio of the dispersion of haze at all measurement points within the local area of ​​each measurement point after the first scan from the dispersion of haze at all measurement points on the standard sample, and calculate the relative fluctuation of haze. The maximum value between the relative fluctuation of transmittance and the relative fluctuation of haze is selected as the anomaly assessment value for the local area where each measurement point is located.

[0009] Preferably, the calculation process for the relative fluctuations in transmittance and haze is as follows: The dispersion of transmittance and haze at all measurement points within a local area is respectively denoted as the local fluctuation of transmittance and the local fluctuation of haze. For the optical thin film under test, the dispersion of transmittance and haze at the corresponding measurement points in the standard sample is calculated based on the location of all measurement points during the first scan. These are denoted as the overall fluctuation of transmittance and the overall fluctuation of haze, respectively. The ratio of the local fluctuation of transmittance to the overall fluctuation of transmittance is taken as the relative fluctuation of transmittance. The ratio of the local fluctuation of fog to the overall fluctuation of fog is taken as the relative fluctuation of fog.

[0010] Preferably, another calculation process for the anomaly assessment value is as follows: For any local area where a measurement point is located, analyze the deviation ratio of the transmittance change gradient at that measurement point relative to the transmittance change on the standard sample, and calculate the relative change in transmittance. Analyze the deviation ratio of the haze change gradient at any measurement point relative to the haze change on the standard sample, and calculate the relative change in haze. The anomaly assessment value is the result of a positive fusion of the relative changes in transmittance and haze.

[0011] Preferably, the calculation process for the relative changes in transmittance and haze is as follows: Based on the transmittance and haze at all measurement points within the local area of ​​any measurement point, the gradient of transmittance and the gradient of haze at the given measurement point are obtained respectively, and the gradient amplitude of transmittance and the gradient amplitude of haze are calculated respectively. Calculate the mean values ​​of the gradient amplitude of transmittance and the mean values ​​of the gradient amplitude of haze at all measurement points on the standard sample, and use them as the reference gradient amplitudes of transmittance and haze, respectively. The ratio of the gradient amplitude of transmittance to the reference gradient amplitude of transmittance is used as the relative change in transmittance. The ratio of the gradient magnitude of fog to the reference gradient magnitude of fog is used as the relative change in fog.

[0012] Preferably, the process of obtaining the abnormal region is as follows: the local area where the measurement point with the abnormal evaluation value is greater than the preset threshold is located is marked as the abnormal region.

[0013] Preferably, the process of obtaining the transmittance distribution map and haze distribution map is as follows: based on the transmittance and haze of all measurement points of the optical thin film under test in two scans, the transmittance and haze are estimated and interpolated using spatial interpolation to generate the transmittance distribution map and haze distribution map of the entire optical thin film under test.

[0014] Secondly, embodiments of this application also provide a light transmittance detection system for optical thin films, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above-described methods for detecting the light transmittance of an optical thin film.

[0015] This application has at least the following beneficial effects: This application rapidly scans the optical thin film under test and analyzes the deviation of its local light transmittance fluctuations from the standard sample. It calculates the anomaly assessment value for the local area and filters out abnormal regions. The advantage lies in accurately identifying areas with suspected abnormal local fluctuations by comparing with the standard sample, thus quickly locating defects and non-uniform abnormal areas of the thin film and ensuring the targeted nature of subsequent fine scanning. A second scan of the abnormal area is then performed at a preset first resolution. Based on the transmittance and haze of all measurement points corresponding to the two scans, a transmittance distribution map and a haze distribution map covering the entire optical thin film under test are generated for light transmittance detection. The advantage lies in that the rapid initial scan and local fine scan mode eliminates reliance on a few sampling points for thin film transmittance detection, enabling a comprehensive assessment of the transmittance and haze across the entire thin film. This significantly improves detection efficiency while maintaining detection accuracy, effectively enhancing the overall performance and reliability of optical thin film testing. Attached Figure Description

[0016] The following is a detailed description of a method for detecting the transmittance of an optical thin film according to the present application, with reference to the accompanying drawings.

[0017] Figure 1 A flowchart illustrating the steps of a method for detecting the transmittance of an optical thin film provided in this application embodiment; Figure 2 A flowchart illustrating the steps of the method for obtaining abnormal evaluation values ​​provided in this application embodiment. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description of a method and system for detecting the transmittance of an optical thin film, in conjunction with the accompanying drawings and embodiments, is provided. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0020] Please see Figure 1 The diagram illustrates a flowchart of a method for detecting the transmittance of an optical thin film according to an embodiment of this application. The method includes the following steps: Step 1: Select a standard sample of the optical thin film and scan it at a preset first resolution to obtain the transmittance and haze of the standard sample at each measurement point; first, perform an initial full-area scan of the optical thin film to be tested at a preset second resolution to obtain the transmittance and haze of the optical thin film to be tested at each measurement point in the first scan.

[0021] Transmittance is an important indicator characterizing the transmission properties of a material, while haze is an important parameter describing the scattering characteristics of transmitted light in transparent and translucent materials, characterizing the material's ability to scatter transmitted light. Transmittance is the ratio of the luminous flux transmitted through the sample to the luminous flux incident on the sample, while haze is the ratio of the scattered luminous flux that passes through the sample and deviates from the incident light direction to the transmitted luminous flux.

[0022] In this embodiment, the optical film is taken as an example of a protective film for automotive display manufacturing. The optical-grade automotive display manufacturing protective film is a PET film temporarily attached to the screen surface during the production and assembly of automotive displays. Due to the inherent fluctuations in the manufacturing process of the protective film, even a protective film with acceptable light transmittance will exhibit certain fluctuations in its light transmittance parameters at different locations on its surface. High-density measurements are performed on standard film samples, specifically: Take a standard sample of optical thin film, fix it flat on the detection platform, and drive the integrating sphere optical probe to perform a high-density grid scan on the entire surface of the standard sample at a preset first resolution. Measure and record the transmittance and haze at each measurement point. In this embodiment, under stable production conditions, optical films without surface defects are screened out, and a sample of a specified size is cut from them. The light transmission uniformity of the sample is tested using interferometry to obtain a standard sample with uniform light transmission. The interferometry method is a well-known technique and will not be described in detail here. Secondly, the preset first resolution value is 0.2 points / mm, that is, a measurement is taken every 5mm. This means that the integrating sphere optical probe moves point by point in the X and Y directions of the surface with a scanning step of 5mm to form a grid-like measurement point array. In other implementation methods, the implementer can set the resolution value according to the actual situation.

[0023] Secondly, for a large-size automotive display protective film, if the scanning measurement is performed directly according to the preset first resolution, the number of measurement points is huge, which is very time-consuming and inefficient. While using only sparse scanning with a large step size is fast, it cannot reliably and comprehensively evaluate the light transmittance of the entire protective film and may miss some tiny defects or uneven areas. Therefore, a multi-level scanning strategy is implemented for light transmittance detection of the optical film under test.

[0024] First, the optical film to be tested is flattened and mounted on the testing platform to eliminate wrinkles and tension. Using an integrating sphere optical probe, the entire surface is scanned with a sparse grid at a preset second resolution. The transmittance and haze at each measurement point during the first scan are measured and recorded. If the preset first resolution is greater than the preset second resolution, the sampling step size used for the preset first resolution is smaller than the sampling step size used for the preset second resolution. In this embodiment, the preset second resolution is 0.05 points / mm, that is, a measurement is performed every 20mm. This means that the integrating sphere optical probe moves point by point in the X and Y directions of the surface with a scanning step of 20mm to form a grid-like measurement point array. In other implementations, the implementer can set the resolution value according to the actual situation.

[0025] Thus, the transmittance and haze at each measurement point on the surface of the standard sample, as well as the transmittance and haze at each measurement point of the optical thin film under test during the first scan, are obtained.

[0026] Step 2: For each measurement point after the first scan, assess the anomaly of the local area by observing the changes and fluctuations in transmittance and haze within the local area, and determine the anomaly assessment value of the local area where each measurement point is located.

[0027] The fluctuations in transmittance and haze on the surface of the standard sample reflect the inherent and unavoidable random non-uniformity of the protective film under qualified production processes. By analyzing the drastic changes in transmittance and haze in local areas on the surface of the optical film under test, anomaly assessment values ​​are calculated to identify areas requiring further high-density scanning, i.e., abnormal areas that may contain defects or non-uniformities. Specifically: For the optical thin film under test, a local area of ​​a preset size is constructed with any measurement point during the first scan as the center; In this embodiment, the local area is a 3×3 grid area, that is, the local area includes the center point and 8 surrounding measurement points, and there are a total of 9 measurement points covering the area, which is the local area.

[0028] The abnormality assessment value of the local area where each measurement point is located is calculated by measuring the degree of deviation of the changes in transmittance and haze at all measurement points in the local area relative to the standard sample. In this embodiment, because the light transmittance parameters of the protective film fluctuate stably and randomly under a qualified production process, following a statistical distribution law, the severity of light transmittance non-uniformity in a local area is illustrated by comparing the measured fluctuations of light transmittance and haze deviation in a local area with the inherent regularity of the standard sample. This reflects the abnormal non-uniformity caused by defects or process drift. The flowchart of the method for obtaining the abnormal evaluation value provided in this embodiment is shown below. Figure 2 As shown, the specific calculation process for the anomaly assessment value is as follows: The dispersion of transmittance at all measurement points within the local area where each measurement point is located during the first scan is calculated and denoted as the local fluctuation of transmittance. For the optical thin film under test, the dispersion of transmittance at the corresponding measurement points on the standard sample is calculated based on the location of all measurement points during the first scan, and is denoted as the overall transmittance fluctuation. The ratio of the local fluctuation of transmittance to the overall fluctuation of transmittance is taken as the relative fluctuation of transmittance. Accordingly, the degree of dispersion of haze at all measurement points within the local area where each measurement point is located during the first scan is calculated and denoted as the local fluctuation of haze. For the optical thin film under test, the dispersion of haze at the corresponding measurement points on the standard sample is calculated based on the location of all measurement points during the first scan, and is denoted as the overall haze fluctuation. The ratio of the local fluctuation of fog to the overall fluctuation of fog is taken as the relative fluctuation of fog. The degree of dispersion is measured by calculating the standard deviation. As another implementation method, the implementer may use other methods of the prior art, such as variance, coefficient of variation, etc. This embodiment does not impose any special restrictions on this.

[0029] The maximum value between the relative fluctuation of transmittance and the relative fluctuation of haze is selected as the anomaly assessment value for the local area where each measurement point is located. It should be noted that, to avoid the denominator being zero when calculating the ratio, a parameter tuning factor is added to the denominator. The range of values ​​for the parameter tuning factor is [range missing]. In this embodiment, the parameter tuning factor is set to 1e-6. In other implementation methods, the implementer can set it according to the actual situation.

[0030] It should be noted that when the light transmittance is uniform in a local area, the fluctuation of light transmittance and haze should be less than or close to the fluctuation benchmark of the standard sample. In this case, the relative fluctuation of light transmittance and haze should be less than or equal to 1, and the smaller the abnormal assessment value, the better. When there are defects or uneven processes in a local area, the light transmittance and haze in that local area will become more dispersed, resulting in a relative fluctuation of light transmittance and haze greater than 1. The larger the abnormal assessment value, the greater the possibility of uneven light transmittance in that local area.

[0031] In another embodiment, the protective film with uniform light transmittance should have a smooth light transmittance parameter field, with its transmittance and haze continuously varying in space. Defects such as scratches, foreign matter, coating streaks, or localized contamination can cause abrupt changes in light transmittance parameters at the edges of the defects. By analyzing the degree of deviation in the spatial variation rate of transmittance and haze at measurement points within a local area, an anomaly assessment value is calculated to evaluate the irregularity of the local area where the point is located, thereby indirectly obtaining the severity of the non-uniformity at that point, and further locating these abnormal areas with sharp transition characteristics. The specific calculation process is as follows: Based on the transmittance at all measurement points within the local area where any measurement point is located, obtain the gradient of transmittance at any measurement point and calculate the gradient magnitude. It should be noted that the gradient represents a vector. Based on the calculation process of gray-level gradient in the image, each measurement point is regarded as a pixel to calculate the gradient of transmittance. The calculation of gradient and gradient magnitude is a well-known technique and will not be elaborated here.

[0032] Based on the fog level at all measurement points within the local area where any measurement point is located, calculate the fog level gradient at any measurement point and calculate the gradient magnitude. Calculate the mean value of the transmittance gradient amplitude at all measurement points on the standard sample, and use it as the reference gradient amplitude of transmittance; Calculate the mean value of the haze gradient amplitude at all measurement points on the standard sample, and use it as the reference haze gradient amplitude; The ratio of the gradient amplitude of transmittance to the reference gradient amplitude of transmittance is used as the relative change in transmittance. The ratio of the gradient magnitude of haze to the reference gradient magnitude of haze is used as the relative change in haze. It should be noted that, to avoid the denominator being zero when calculating the ratio, a parameter tuning factor is added to the denominator. The range of values ​​for the parameter tuning factor is [range missing]. In this embodiment, the parameter tuning factor is set to 1e-6. In other implementation methods, the implementer can set it according to the actual situation.

[0033] The relative changes in transmittance and haze are positively fused to form the anomaly assessment value for the local area where any measurement point is located. The specific process of positive fusion is as follows: the square root of the sum of the squares of the relative changes in transmittance and the relative changes in haze is used as the anomaly assessment value.

[0034] It should be noted that the gradient amplitude reflects the degree of drastic change in transmittance and haze at the measurement point along the spatial direction. In local areas where the protective film has uniform light transmission, the changes in transmittance and haze are gradual, and the gradient amplitude approaches zero, resulting in a lower anomaly assessment value. When the measurement point is located near the boundary of a defect, both transmittance and haze will change significantly within a short distance, causing the calculated gradient amplitude to increase sharply. This results in a larger anomaly assessment value, indicating a greater possibility of uneven light transmission in that local area.

[0035] Thus, the anomaly assessment values ​​of the local regions where each measurement point on the optical thin film under test is located are obtained.

[0036] Step 3: Based on the abnormal evaluation value, the abnormal area is screened out; then the abnormal area is scanned a second time at a preset first resolution. Based on the transmittance and haze of all measurement points corresponding to the two scans, a transmittance distribution map and a haze distribution map covering the entire optical film under test are generated to detect its transmittance.

[0037] Furthermore, based on the anomaly assessment values, abnormal regions are selected, specifically: The local area where the measurement point with an abnormal evaluation value greater than the preset threshold is located is marked as an abnormal area; In this embodiment, the process of obtaining the preset threshold is as follows: For the standard sample, the abnormal evaluation value of each measurement point on the standard sample is obtained according to the above method. The abnormal evaluation values ​​of all measurement points on the standard sample are arranged in ascending order, and the abnormal evaluation value corresponding to the 99th percentile is selected as the preset threshold. The 99th percentile is a well-known technique and will not be described in detail here.

[0038] It should be noted that if the abnormal evaluation value of each measurement point on the optical film under test is calculated using the method of the first embodiment, then the abnormal evaluation value of all measurement points on the standard sample is also calculated using the calculation method of the first embodiment to obtain the preset threshold; if the abnormal evaluation value of each measurement point on the optical film under test is calculated using the method of the second embodiment, then the abnormal evaluation value of all measurement points on the standard sample is also calculated using the calculation method of the second embodiment to obtain the preset threshold.

[0039] According to the preset first resolution, the abnormal area in the optical film under test is scanned a second time, and the transmittance and haze at each measurement point are measured and recorded during the second scan. Furthermore, based on the transmittance and haze of all measurement points during the two scanning processes of the optical thin film under test, spatial interpolation methods are used to estimate and generate transmittance distribution maps and haze distribution maps of the entire optical thin film under test, so as to detect the transmittance of the film. In this embodiment, the spatial interpolation method used is Kriging interpolation. The first scan yields low-resolution global data, while the second scan yields high-resolution local data. Therefore, the transmittance of all measurement points in the first scan is used as an auxiliary variable, and the transmittance of all measurement points in the second scan is used as the primary variable. A variogram is established between the primary and auxiliary variables based on the spatial distribution of the sample points. This variogram is then used to estimate the transmittance at other locations, thus generating a transmittance distribution map. Similarly, the haze of all measurement points in the first scan is used as an auxiliary variable, and the haze of all measurement points in the second scan is used as the primary variable. A variogram is established between the primary and auxiliary variables based on the spatial distribution of the sample points. This variogram is then used to estimate the haze at other locations, thus generating a haze distribution map. Kriging interpolation is a well-known technique and will not be elaborated upon here.

[0040] The process for detecting light transmittance is as follows: In this embodiment, the area of ​​regions with transmittance less than a preset lower limit threshold in the transmittance distribution map is used as the ratio of the area to the total area of ​​the optical film under test, and the ratio of the area to the total area is used as the proportion of low transmittance defects. The area of ​​regions with haze exceeding the preset upper limit threshold in the haze distribution map is used as the ratio of the area of ​​the region to the total area of ​​the optical film under test, and the ratio of the area of ​​the region to the total area of ​​the optical film under test is used as the proportion of high haze defects. The preset lower limit threshold for light transmittance and the preset upper limit threshold for haze are usually determined by the product specifications of the optical film. For a protective film that requires a light transmittance of not less than 92% and a haze of not more than 1.0%, the preset lower limit threshold for light transmittance is set to 92% and the preset upper limit threshold for haze is set to 1.0%. As other implementation methods, implementers can set them according to the actual situation.

[0041] If the proportion of low light transmittance defects or high haze defects exceeds the preset value, the overall light transmittance uniformity of the optical film under test is unqualified; otherwise, it is qualified. The preset value is 1%. As for other implementation methods, the implementer can set it according to the actual situation.

[0042] In another embodiment, the standard deviation of all transmittance is calculated for the transmittance distribution map of the optical thin film under test; For the haze distribution map of the optical thin film under test, calculate the standard deviation of all haze values; If the standard deviation of the transmittance of the optical film under test is less than or equal to the standard deviation of the transmittance of the standard sample, and the standard deviation of the haze of the optical film under test is less than or equal to the standard deviation of the haze of the standard sample, then the overall transmittance uniformity of the optical film under test is qualified; otherwise, it is unqualified.

[0043] Based on the same inventive concept as the above method, this application embodiment also provides an optical thin film transmittance detection system, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above-described optical thin film transmittance detection methods.

[0044] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0045] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0046] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application, without departing from the content of the technical solution of this application, shall fall within the protection scope of the technical solution of this application.

Claims

1. A method for detecting the transmittance of an optical thin film, characterized in that, The method includes the following steps: A standard sample of optical thin film is selected and scanned at a preset first resolution to obtain the transmittance and haze of the standard sample at each measurement point; For the optical thin film under test, a multi-level scanning strategy is executed, the strategy including: First, a preliminary full-area scan of the optical film under test is performed at a preset second resolution to obtain the transmittance and haze of the optical film under test at each measurement point in the first scan. By analyzing the degree of deviation of the changes in transmittance and haze at all measurement points within the local area of ​​each measurement point after the first scan relative to the standard sample, the abnormal evaluation value of the local area of ​​each measurement point is calculated to screen out abnormal areas. Then, the abnormal area is scanned a second time at a preset first resolution. Based on the transmittance and haze of all measurement points corresponding to the two scans, a transmittance distribution map and a haze distribution map covering the entire optical film under test are generated to detect its transmittance.

2. The method for detecting the transmittance of an optical thin film as described in claim 1, characterized in that, The preset first resolution is greater than the preset second resolution.

3. The method for detecting the transmittance of an optical thin film as described in claim 1, characterized in that, One calculation process for the anomaly assessment value is as follows: Analyze the deviation ratio of the transmittance of all measurement points in the local area where each measurement point is located after the first scan from the transmittance of all measurement points on the standard sample, and calculate the relative fluctuation of transmittance. Analyze the deviation ratio of the dispersion of haze at all measurement points within the local area of ​​each measurement point after the first scan from the dispersion of haze at all measurement points on the standard sample, and calculate the relative fluctuation of haze. The maximum value between the relative fluctuation of transmittance and the relative fluctuation of haze is selected as the anomaly assessment value for the local area where each measurement point is located.

4. The method for detecting the transmittance of an optical thin film as described in claim 3, characterized in that, The calculation process for the relative fluctuations in transmittance and haze is as follows: The dispersion of transmittance and haze at all measurement points within a local area is respectively denoted as the local fluctuation of transmittance and the local fluctuation of haze. For the optical thin film under test, the dispersion of transmittance and haze at the corresponding measurement points in the standard sample is calculated based on the location of all measurement points during the first scan. These are denoted as the overall fluctuation of transmittance and the overall fluctuation of haze, respectively. The ratio of the local fluctuation of transmittance to the overall fluctuation of transmittance is taken as the relative fluctuation of transmittance. The ratio of the local fluctuation of fog to the overall fluctuation of fog is taken as the relative fluctuation of fog.

5. The method for detecting the transmittance of an optical thin film as described in claim 1, characterized in that, Another calculation process for the anomaly assessment value is as follows: For any local area where a measurement point is located, analyze the deviation ratio of the transmittance change gradient at that measurement point relative to the transmittance change on the standard sample, and calculate the relative change in transmittance. Analyze the deviation ratio of the haze change gradient at any measurement point relative to the haze change on the standard sample, and calculate the relative change in haze. The anomaly assessment value is the result of a positive fusion of the relative changes in transmittance and haze.

6. The method for detecting the transmittance of an optical thin film as described in claim 5, characterized in that, The calculation process for the relative changes in transmittance and haze is as follows: Based on the transmittance and haze at all measurement points within the local area of ​​any measurement point, the gradient of transmittance and the gradient of haze at the given measurement point are obtained respectively, and the gradient amplitude of transmittance and the gradient amplitude of haze are calculated respectively. Calculate the mean values ​​of the gradient amplitude of transmittance and the mean values ​​of the gradient amplitude of haze at all measurement points on the standard sample, and use them as the reference gradient amplitudes of transmittance and haze, respectively. The ratio of the gradient amplitude of transmittance to the reference gradient amplitude of transmittance is used as the relative change in transmittance. The ratio of the gradient magnitude of fog to the reference gradient magnitude of fog is used as the relative change in fog.

7. The method for detecting the transmittance of an optical thin film as described in claim 1, characterized in that, The process of obtaining the abnormal region is as follows: the local area where the measurement point with the abnormal evaluation value is greater than the preset threshold is marked as the abnormal region.

8. The method for detecting the transmittance of an optical thin film as described in claim 1, characterized in that, The process of obtaining the transmittance distribution map and haze distribution map is as follows: based on the transmittance and haze of all measurement points of the optical thin film under test in two scans, the transmittance and haze distribution maps of the entire optical thin film under test are estimated and interpolated using the spatial interpolation method to generate the transmittance distribution map and haze distribution map of the entire optical thin film under test.

9. A transmittance detection system for an optical thin film, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method for detecting the transmittance of an optical thin film as described in any one of claims 1-8.

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